Field of the Invention
Embodiments of the present invention relates to a display technology field, more particularly, relates to a display panel and a display apparatus.
Description of the Related Art
With development of display technology and increasing demand on portable electronic products, in recent years, persons in this art are focusing attention on a transparent display apparatus, which can display an image thereon and allow an object at the back of the display apparatus to be visible from the front of the display apparatus.
So far, although there are many kinds of materials adapted to achieve a transparent display, a preferable transparent display material comprises cholesteric liquid crystal because the cholesteric liquid crystal possesses unique characteristics. The cholesteric liquid crystal contains many layers of cholesteric liquid crystal molecules, and each layer of cholesteric liquid crystal molecules has the same arrangement direction. The cholesteric liquid crystal molecules are laminated in a layer-by-layer way to form a spiral structure. When the arrangement direction of the cholesteric liquid crystal molecules is rotated from an initial orientation by 360 degrees to return to the initial orientation again, the spiral structure goes through a spiral pitch. Depending on spiral direction, the cholesteric liquid crystal is classified into a left-handed cholesteric liquid crystal having a left-handed circular polarization and a right-handed cholesteric liquid crystal having a right-handed circular polarization. When the cholesteric liquid crystal exhibits a planar texture state distribution, the cholesteric liquid crystal has a selectively reflective characteristic. In such a case, the left-handed circular polarization is capable of reflecting a left-handed circularly polarized light having a wavelength similar to the pitch of the cholesteric liquid crystal, but permitting the right-handed circularly polarized light and a light having a wavelength different from the left-handed circularly polarized light to pass therethrough. The right-handed circular polarization is capable of reflecting a right-handed circularly polarized light having a wavelength similar to the pitch of the cholesteric liquid crystal, but permitting the left-handed circularly polarized light and a light having a wavelength different from the right-handed circularly polarized light to pass therethrough. When the cholesteric liquid crystal molecule is rotated by 90 degrees to become a vertical texture state distribution, that is, when a direction in which the cholesteric liquid crystal molecule extends is parallel to an incident direction of a light, both the left-handed circularly polarized light and the right-handed circularly polarized light can pass through the cholesteric liquid crystal. Because of the above characteristics of the cholesteric liquid crystal, the cholesteric liquid crystal is generally applied in a transparent display panel, and a backlight source that can emit a light having a wavelength similar to the pitch of the cholesteric liquid crystal is adopted to provide a backlight for the transparent display panel, so as to achieve a normal display of the transparent display panel. Also, an ambient light having a wavelength considerably different from the pitch of the cholesteric liquid crystal can pass through the transparent display panel, so as to keep the transparent effect of the transparent display panel.
However, as for the transparent display panel of cholesteric liquid crystal in the prior arts, in order to achieve the normal display of the transparent display panel, it generally needs to provide a drive electrode to drive the cholesteric liquid crystal to deflect. However, a drive voltage, which is applied to the drive electrode to drive the cholesteric liquid crystal to deflect, is very high. For example, the drive voltage is often set to be 40V or more. Accordingly, the high drive voltage of the cholesteric liquid crystal limits the wide application of the cholesteric liquid crystal in the display field.